calc_outdist: Update flow length from the upstream node of each stream segment
to the outlet of the network .
Description
Recursive function to calculate the flow length from the
upstream node of the stream segment to the outlet of the network.
It is called by delete_lakes for each
outlet and should not be called by the user.
Usage
calc_outdist(dt, id)
Arguments
dt
data.table containing the attributes of the stream segments